DIY cheap charger from balance wires

[migueralliart]

no. the input voltage goes into a buck converter that makes the current that goes out to the battery. the output of that buck converter is isolated from the input from the battery you use to charge it. so each of the balance chargers could be hooked up to the 12V battery and it would charge the full 15S if you had 3 of them in series.

except the lowest wire in the sense wire plug will be the negative of the first cell so the second sense wire cable will have that first wire connected to the top of the sense wire cable underneath it.

Ok I understood that perfectly ! just wanted to know if they were isolated.

Will order 3 of those and test them on a 18S lifepo4 pack and 15S li-io pack. Will see how it goes. I don't think they are 5A units at 6S charging but I'll put em to the test. With 3 of em you could potentially balance charge up to 18S lipo . For the 12V supply I'll use a modified HP server supply I have laying around.

 

[dnmun]

i bet you can use up to 20-24V if you wanna. they may say 18V for the upper limit. the higher the voltage the more current it will push i expect.

open them up when you get it and we can look for you too. you may be able to tweak it for higher input voltage and more charging current.

 

[migueralliart]

i bet you can use up to 20-24V if you wanna. they may say 18V for the upper limit. the higher the voltage the more current it will push i expect.

open them up when you get it and we can look for you too. you may be able to tweak it for higher input voltage and more charging current.

Well I got 3 of these 6S balancers a while ago but didn't have time to open them up just in case here is one picture.



Edit :

Looking a bit on the input side I can see there is a 25V cap in there.
There's also a ATMEGA32A and a 6 pin header ?